This invention relates to the field of liquid heating vessels in general, but is particularly suited to kettles.
It is known in liquid heating vessels, such as kettles, to provide a means of illumination circumferentially around the liquid heating vessel so that the operational condition of the kettle is visible to a user from any direction.
UK patent application GB-A-2,312,153 discloses a kettle with a housing, wherein a light emitting device is located within the bottom of the housing. Light is guided from the light emitting device by an optical conductor to be visible circumferentially of the housing.
International patent application WO-A-00/24300 also discloses a kettle which has a light emitting device located within the bottom of a housing. Light is guided from the light emitting device by a moulded plate to be visible circumferentially of the housing.
Both of the above inventions require complex mouldings and extra components to provide a means of guiding the light from the light emitting devices to the circumference of the kettle. The complex mouldings and extra components contained within the above kettles add to the cost and complexity of their manufacture.
According to the present invention there is provided a liquid heating vessel comprising:
a housing; and
one or more light emitting devices disposed within said housing and positioned relative to respective holes in said housing such that, in use, said one or more light emitting devices project light through said holes onto a surface outside of said housing, said light being reflected from said surface outside of said housing to be visible to a user.
Because the light emitting devices are positioned to project light directly through the holes there is no requirement for any device or structure that has the function of guiding or conducting the emitted light to the holes. This arrangement gives the advantage of reducing the complexity and cost of manufacture of the liquid heating vessel.
The light could be protected on to any surface outside of the vessel, such as a wall or work surface. However in accordance with preferred embodiments, the light is reflected from an outer surface of the housing. Reflecting the light that exits the holes from an outer surface of the housing enables a desired visual effect to be readily achieved and provides the ability to give a patterned effect.
While it will be appreciated that the liquid heating vessel may be formed out of a single continuous part, it is preferred for the housing to comprise a main body and a stand wherein the stand is a power supply stand via which electrical power is provided to the liquid heating vessel.
While it will be appreciated that the light emitting devices may be placed in the stand, preferred embodiments of the invention recognize that the cabling from the activating switch in the handle to the light emitting devices can be omitted if the light emitting devices are placed in the base portion of the main body of the liquid heating vessel, thereby reducing the complexity and the cost of manufacture of the liquid heating vessel.
A pleasant aesthetic effect can be achieved if light radiates circumferentially from the bottom of the liquid heating vessel. To accomplish this light, emitting devices may be deployed in the base of the main body so that they project light out of the holes in the base of the main body that is then reflected by the outer surface of the stand to be visible to the user.
While it will be appreciated that the light emitting devices could take many different forms, e.g. neon bulbs, incandescent bulbs or light emitting diodes, the preferred light emitting device is a light emitting diode (LED). Light emitting diodes have the advantages that they are bright, reliable and have low heat output. Light emitting diodes are available that can emit light that is directed within a cone of small solid angle, which may assist the projection effect. Superluminescent light emitting diodes or lasers may be preferred as they emit very intense light compared to standard LEDs.
In preferred embodiments, the LEDs pulse in response to a predetermined operational condition of the liquid heating vessel, e.g. the LEDs can be lit continuously when the liquid heating vessel is heating a liquid to bring the liquid to a boil and the LEDs can flash when the liquid is being heated at a reduced rate to maintain the liquid temperature once the liquid has boiled.